Walking angle corrective footwear



Nov. 4, 1952 R. u. DARBY WALKING ANGLE CORRECTIVE FOOTWEAR 2 SHEETS- SHEET 1 Filed June 14, 1946 1N VENTOR Reuben U- czy2 ATTORNEY Nov. 4, 1952 R. u. DARBY WALKING ANGLE!v CORRECTIVE FOOTWEAR 2 SHEETS-SHEET 2 Filed June 14, 1946 INVENTOR 52 Reu/bn Z-[Dary BY ATTORNEY Patented Nov. 4, 1,952

UNITED STATES PATENT OFFICE WALKING ANGLE CORRECTIVE FOOTWEAR Reuben U. Darby, Middletown, Md.

Application June 14, 1946, Serial No. 676,691

3 Claims.

This invention relates to the correction of human foot' and leg disorders arising from incorrect weight bearing on the feet.

The lower extremity has a combination of small bones in the foot which are connected together by ligaments and muscles. The stronger muscles separating and controlling the movements of .the foot are attached to the two bones above the ankle. These bones are known as the tibia and the bula. The larger and medial bone1 the tibia, has two functions, weight bearing and attachment for muscles supporting and controlling the feet. The lateral and smaller bone, the fibula, serves principally for muscle attachment. The tibia, or larger and two-function bone, is fiat in front and has two margins, a medial and lateral one. The lateral margin if extended downward passes through the center of the talus, the rst supporting bone of the foot, and through the center of the ,foot or slightly lateral to center on the small toe side. This is a normal walking angle. If this line passes medial Vto center or to the big toe side, the person has an incorrect walking angle which causes extra strain on the muscles and ligaments of the entire lower extremity, eventually throwing the whole skeletal system out of balance.

The invention provides for correcting this walking angle in the course of walking by elevating the medial side of the shoe or other footwear with an elevated outer fore-sole and heel, lby means of separate non-integrally or integrally formed partial outer lift portions, for the medial side of the footwear in or on the bottom of the outer fore-sole and heel `of the footwear of the on the medial side of the foot by the single upward motion vof the bones on the medial side of the foot, unaccompanied by attendant rocking motion of the upper leg members, or twisting of the foot or shoe, and before the weight of the wearer is transmitted to the lfoot by the weight bearing members of .the leg above the foot in the process of ambulation, thus correcting the walking angle. The amount of elevation iscorrected to each individuals need. When a person'places his foot in walking, yhis walking angle is corrected in perfect alignment with the bones of the leg, by the single upward thrust-movement that takes place upon the initial implanting of the shoe before the weight of the body is shifted over onto the advancing footof the wearer in walking.

Alteration of the correct walking .anatomical angle may produce a .whole chain ofrdeformities :5,5

and disabilities. For instance, the arches of' the wearer, so as to effect an adjustment of the bones foot may be looked upon as arcs which are concave downwardly and convex upward. There are transverse and longitudinal arches. Normally, the outer portion of the longitudinal arch is very low and almost rests on the ground. The inner part is high and only touches the ground behind. Normally there is a series of transverse arches extending from the arch formed by the heads of the metatarsals back to the arch formed by the navcular and the cuboid. The inner border of the foot is naturally straight, or concave inwards when weight is being borne. A vertical line dropped from the head of the femur through the patella and along the crest of the tibia should pass normally through the second intermetatarsal space (between the second and third toes) counting from the right hand side, viewing Fig. 1. Alteration of the correct walking angle, such as occurs in the case of flat-foot, results in the forefoot being deflected laterally, the arch drops and becomes flattened, and the inner border which should normally show a slight concavity is replaced by convexity and the vertical line dropped from the head of the femur through the patella along the crest ofthe tibia, instead of normally passing through the second intermetatarsal space (between the second and third toes) passes internal Ato this space, toward the big toe side.

In correction of this, it would appear that this could be simply provided for by slightly elevating the medial side of the footwear of an individual requiring walking angle correction. This seemingly is most readily and simply done by means of arch supports and/ or removable inner-sole inserts providing elevation for the heel and forepart of the foot, as required on the medial side of `the footwear of the individual. However, it

4has been found in practice that While such foresole and heel inserts, ,and ,arch supports, elevate the medial side of the foot, their use in practice is ,accompanied by other movements which defeat the intendedcorrection of the Walking angle, and introduce new and different discomforts to the wearer. For example, arch supports, in use by the wearer, exert upward pressure on the keystone of the arch tending to loosen it in an upward direction so that the transverse and longitudinal arches tend to collapse, the extremities being drawn toward each other by the muscles of the sole of the foot and the plantar fascia. lMoreover, ythe weight of the body is by such arches transmitted from the talus directly to the shank of the footwearrather than as normally through the heel and the heads of the first and fifth meta- 3 tarsal bones to the outersole of the footwear and thence to the ground.

When such elevation correction is attempted by means of inserts in the form of inner-soles, it will be found that while such inner-sole elevation on the median side of the foot for the heel and foresole will elevate the bones of the foot as contemplated, in practice it will be found, however, that the walking angle nevertheless is not corrected and, as in the case of arches, their use in practice is accompanied by other movements which introduce new and different discomforts to the wearer. Y

It has been found that due to the rise and fall of the sole of the foot relative to the sole of the footwear, in walking, the elevation of the median side of the foot by means such as innersoles which are raised or elevated on one side at the heel and foresole, is accompanied by' a rocking motion. A dualmovement takes place vin which, Vfor instance, the tibia and bula rock laterally relative to the talus, thus introducing new discomfort, and resulting in a new and different incorrection of the normal anatomical walking angle.

Y VWhere attempt to correct the walking angle, by use of such partial lifts for the median side of the foresole and heel, is `made by attachment Y outline of the footwear.

of such partial lifts to the outer bottom surface of the foresole and heel of footwear, a like dual motion is found to take place, and thus correction of the walking angle by such means seemingly is defeated by other accompanying movements of the foot and footwear relative Ato each other that take place in the normal course of ambulation.

Y In development of the present invention it has been discoveredthat while the employment of such partial lifts on the exterior bottom surface of the median side of the foresole and heel of the footwear is accompanied, as in the case of innersoles, by a, dual movement, the additional movement which occurs is not equivalent but is instead a twisting movement of the shoe or footwear rather than a rocking movement of the upper limb members. It has further been Afound that the twisting movement is not a definitely discomforting movement, but merely aesthetically annoying, and moreover, it has been found that such employment of partial lifts for the purpose on the bottom of the sole and heel does not defeat the end of correcting the walking angle of the wearer in the course of ambulation.V

It has still further been found in the development of the instant improvement in aid of simply and economically correcting the walking angle of persons requiring such aid, that when vthe partial lifts are employed as partial interlifts which are intermediate the upper surface of the bottom lifts of the fore out-sole and heel, and the bottom surface of the insole of the outer sole structure of footwear, that the aforesaid disadvantages are avoided and the action of correcting the walking angle takes place with a, single movement rather than a dual movement. Supercially there wouldseem to be no fundamental difference in structure or function. However, with many patients who have been tted vwith the three types for the purpose, in use it has been found to be amaterial and substantial difference in result insofar as correction of the vwalking angle and attendant comfort to the weary er is concerned. Y

In accordance with the present invention there is provided for the footwear of individuals requiring correction of their walking angle, a partial outer-sole lift comprising separate outer foresole and heel lift portions for the medial (inner) side of the footwear. Each partial lift portion extends from the median line, or longitudinal central plane, of the shoe or footwear to the inner (medial) side margin of the same, and each is inclined to increase in depth from the inner median line to the inner margin of the footwear, where it is shaped to conform with the The foresole lift portion extends from the tip of the cap of the forepart of the footwear back to the front line of the shank, and the heel portion extends from the rear line of the shank to the back counter extremity of the heel of the footwear. The amount of elevation at the inner margin relative to the extremity at the central line of the footwear will vary according to the needs of the individual to whom the corrective is to be fitted, and of course each foretip and rear heel-portion is tapered in conformity with conventional shaping of the sole of the footwear. The amount of elevation chosen is selected so that, when fitted to a person whose foot is so shaped that a line dropped vertically from the patella along the crest of the tibia passes medial to center or to the big toe side, the elevation is sufficient to elevate the medial side of the forefoot and heel so that the vertical line then will pass through the center of the foot (between the second and third toes) or slightly lateral to center on the small toe side.

The partial outer-lift portions are, in accordance with the objects of invention, applicable in several ways to the footwear. For new shoes or other new footwear, the partial lifts are, or may be, incorporated in the ori-ginal manufacture of the shoes or other footwear by assembling the separate but non-integral inserts or slips between the lower surface of the insole, or equivalent, to which the upper is attached, and the upper surface of the bottom-lift of the out sole or tread portion of the outer-sole structure of the footwear. Alternatively, the separate partial outer lift portions may be formed as an integral part of either the lower surface of the insole (or equivalent) or the upper surface of the bottom outsole lift or tread portion ofthe footwear, or, when the twisting action of the footwear is not objectionable the partial lift portions may then, within the contemplation of the invention be disposed on thebottom surface of the tread portion of the outer sole of the footwear, as by attachment as separate non-integral lift portions, orelse formed as a separate but integral part, as by molding of composition outer lifts.

However, the invention contemplates the incorporation ofthe novel partial outer-sole lift portions, to both new and old shoes or footwear of conventional or standard commercial types by manufacturing the lift portions in different sizes and thicknesses, as non-integral' separate articles of manufacture for application Vtoold or new footwear by fitting and incorporation of them as inserts between in and out sole lifts, or as added sub-lifts for the bottom surfaces of the out soles of footwear, by ordinary skilled shoe or footwearrepairers, as well as orthopedists. Y

An advantage of the novel outersole partial lifts for footwear. and method. of the present invention is that .of its .simplicity and economy, f as well as full eifectvenes'sv for its intended anaitomical correcting purpose.-

"rhe features of invention may 'readily and easily be incorporated i'n the original ianu'facture of the shoe or footwear from the sai'n'hiaterials contemplated for the manufacture of the rest of the sole structure of rthe footwear, with'- out modification of the process of 'manufacture of the rest of the footwear; and moreover the feature of invention after being applied 'to the article for wear is in a vperma'net and fixed felation relative to the rest of the footwear Aand foot of the wearer, and involves "no losnes's, 0r slipping or chaiing. The features of invention are of particular merit and advantage for appli* cation to fabricated new and old footwear, in full accordance with the needs 'of individual wearers, by ordinary skilled footwear repairers, as well as orthopedists, since the novelty of the invention is so simple that its technique can be explained in ordinary lay language, and the'av'- erage shoe repairer taught in a f'e'w minutes the correct manner of fitting, and the partial lifts can be prepared and incorporated in the foot;- wear of the average person in as little asfifteen minutes to a half hour.

The invention has for further objects such other improvements and such other operative advantages or results as may be found to obtain in the structure and method hereinafter described and claimed.

In the accompanying drawing forming a part of this specification, and showing for purposes 'of exemplification, the preferred form and manner of embodying and practicing the invention:

Figure 1 is a diagrammatic view illustrating the correct relationship of the bone structure of the human leg relative to the center of the foot, that is, the second intermetatarsal space, to wit, between the second and third toes, counting from the big toe side.

Figure 2 is a like view but illustrating the alteration in correct anatomical walking angle, which occurs as in the instance of so-called fiatfoot, in which case a vertical line dropped from the head ofthe femur through the 'pateila along the crest of the tibia passes medial to center, to the big toe side, resulting in an incorrect walking angle which causes extra Astrain on the muscles and ligaments, and eventually throws the whole skeletal system out of balance through the gluteus medius.

Figure 3 is a front elevational view of 'a shoe embodying one form of the present invention, in which the novel element, is integral with the sole.

Figure 4 is a like front elevational View of a shoe embodying another form of the present invention in which the separate novel element is formed as a unit non-integral with other parts of the whole outsole. l

Figure 5 is a perspective view ofthe heel portion and Fig, 5a is a perspective view of the foresole portion of the outer-sole partial-lift, as used in the construction illustrated in Fig. 4.

Figure 6 and Fig. 6A are views similar to Figs. 5 and 5A, but illustrating the partial lift portions, as used in the construction illustrated n Fig. 3, wherein they are embodied as integral parts of the half sole and heel of the shoe of Fig. 3.

Figures 7 and 'la are cross-sectional views through the foresole and heel portions respectively of a shoe as in Fig. 3, but with the partial lifts of the invention attached to the exterior.

on the bottom surface of theiowermost tread liftnof the foresole and heel.

Figures -8 and 8a are like cross=sectional views vthrough Fig. 4, further illustrating the preferred embodiment of this invention.

In accordance with the present invention, for commercial application of the novel principles of the present improvement, there are provided two 'forms of construction, the form illustrated in Figs. 3i 6 and '6d being preferred, and the form illustrated in Figs. 4, 5` and 5a being next preferred.

both forms, there is provided a partial outsole lift 'comprising a foresole portion 46 and a heel lift portioiiv 41 for the medial side 42 of the 'Whole out-sole structure 48 of footwear,

The foresole lift portion comprises 'anoutsole lift member having opposite 'extremities 49 and 50 coinciding with-the median line and the me dial marginal line respectively, of footwear, and a `rear extremity 5l and 'forward extremity '52 coinciding with the front line of the shank and the tip of the cap forepart, respectively, offoo'twear, such as shoes, sandals, slippers, boots and the like.

The heel-lift portieri 41 comprises a lift member for the outsole structure 48 having like opposite side extremitiesAB and 50 coinciding with the median line and medial marginal line of the heel of footwear. The heel-lift portion also has forward and rear extremitiesla and 52a coinciding with the rear line of the shank and back edge of the heel portion of footwear respectively. Each portion is tapered toward the medial 'and marginal side extremity, to provide 'the progressive elevation, in the direction of the medial mai'- ginal side extremity., required to suit the needs of the individual in elevating the side of the lfoot on the inner side to shift 'the line of projection of a vertical line dropped from the patella 31 along the crest of the tibia 38 laterally ltoward the little toe side, so as to pass through the center of the foot or slightly lateral to center on 'the small toe side and thus correct the Walking angle.

Iny the preferred embodiment of the invention the portions 46 and 41 are constructed to constitute inters'oleelift portions as in Figs. 3, 4, 8, and 8a, 9a. Alternatively they are also constructed to constitute added sub-lifts as shown in Figs. 77a, where the twisting action is not objectiona le. f

Advantageously the partial lifts 4S and 41 of inventionare formed as pre-formed elements as illustrated in. Figs. 5 and 5a, for application 'as units to separate and independent full half-sole lifts and full heel lifts customarily used in commerce, as illustrated in Figs. 8 and 8a.

Preferably, however, they are formed as integral parts of the full halfsole section and of the full heel section of the whole outsole structure for footwear, .for instance, as shown Vthey are formedr as `.an `integral.#part of a halfsole and a heel, by casting as a single unitary Whole in a mold as from mastic or plastic composition material. It is considered better to have them formed with a horizontal bottom surface and their upper surface inclined as shown in Figs. 3 and 6 and 6a to constitute the upper surface of the slips or intersoles, or added sub-lift. The invention in its broader aspects also lcontemplates casting them as a unitary whole with the bottom surface of the insole, or equivalent, to which the upper of footwear is conventionally attached, and also to the bottom surface of the lowermost tread or lift in the relationship exemplified in 7 Figs. 7V4 and 7a, which may be done by turning the elements of Figs. 6, 6a, upside down, and using them so that the members 46 and 41 are still on the medial sides of the shoes, but for the other foot from which they normally are used, when the elements are employed as in Fig. 3.

In the embodiment of the invention shown in Figs. 3, 6, 6a, the novel partial lifts of invention are shown as formed, by casting in a mold, as a single unit with a full half sole and full heel lifts. The full half sole section and full heel section, with the integral lifts, are assembled with the insole 56, to which the upper 51 is attached, so as to have the partial'lifts equivalent to inter-soles or slips in the whole out-sole structure, in which case they have the same orientation as that shown in Figs. 8 and 8a.

In the embodiment shown in Figs. 4, 5, a, 8 and 8a, the elements shown in Figs. 5 and 5a are fitted to the vwhole out-sole structure as previously non-integrally formed separate inter-sole lifts between the upper surface of the wear members and the bottom surface of the insole 56 to which the upper 51 is attached as conventionally. 58 indicates a conventional heel base and 59 a removable innersole inserted within the upper 51.

It has been found that for proper correction, conjoint elevation of the heel as well as the foresole is essential. However, the preformed foresole partial lifts may, in instances, be used Without use of preformed partial heel-lifts, where the Vheel elevation is a minor one and may be built up by use of small pieces of scrap. Likewise, in in stances, the preformed heel partial-lifts may be used without use of preformed foresole partiallifts. where the foresole elevation is a minor one Vand may be obtained by use of scrap.

However, to attain the full advantage of the invention, in the conjoint use of the partial lifts for the foresole and the heel, the forward terminal extremity of the partial heel lift and the rear terminal extremity of the foresole partial-lift portions should coincide with the lines of the rear vand forward extremities of the shank of the footwear, since the full advantage of restoring the .normal orientation and structure of the arch of .the foot becomes offset if the shank of the footwear is provided with artificial arch elevations, since they tend to unlock or loosen the arch by raising the talus, which acts as the interlocking keystone of the arch, and is defeated in so doing when elevated by supports at the shank region.

The invention as hereinabove set forth is embodied in a particular form and manner but may be variously embodied within the scope of the following claims.

I claim: Y

1. A walking angle corrective element for footwear comprising, a shoe halfsole comprising a generally flat body including a nat normally outer face and an inner face having a generally flat area along one longitudinal side of the body coinciding with the outer lateral side of a shoe for which the halfsole is` designed to be applied from its median line to its outer lateral marginal edge, the remaining portion of the inner face along the opposite longitudinal side of the body having a raised portion coinciding with the medial side of said shoe and having opposite side terminal extremities coinciding with the median line and the medial side marginal line, and forward andvrear terminal extremities coinciding with the line of the tip and the forward line of the shank, respectively, of the outsole structure of said shoe, said raised remaining portion of the inner face being inclined upwardly and outwardly from the said area to the opposite medial longitudinal edge of the body from the tip line to the forward shank line extremities.

2. A walking angle corrective element for footwear comprising, an outsole full foresole lift portion having a flat face on one side thereof and having formed on its opposite face a tapered partial foresole lift portion, said partial lift portion having opposite side terminal extremities respectively coinciding with the median line and the medial side marginal line, and having forward and rear terminal extremities coinciding with the line of the'tip' and the forward line of the shank respectively, of the outsole structure of footwear to-which the element is designed to be applied, said partial lift portion being of greater height at the region of its medial marginal portion than at the region of its median line portion, to raise the inner side of the forepart of the human foot the required distance for correcting the walking angle."

3. A structure as defined in claim 1 wherein said walking angle rcorrective element is integrally formed with a half sole of the footwear.

R. U. DARBY.

REFERENCES CITED The following references are of record in the i'lle of this patent:

UNITED STATS PATENTS v Y vOTHER REFERENCES Shoe Service (Magazine) Feb. 1941, pp. 13, 30, 

